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		<title>three.js webgl - custom attributes [particles][billboards][alphatest]</title>
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				background-color: #000000;
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			#info {
				color: #fff;
				position: absolute;
				top: 0px; width: 100%;
				padding: 5px;
				z-index:100;
			}

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	<body>
		<div id="info"><a href="http://github.com/mrdoob/three.js" target="_blank">three.js</a> - custom attributes example - particles - billboards - alphatest</div>
		<div id="container"></div>

		<script src="../build/Three.js"></script>

		<script src="js/Detector.js"></script>
		<script src="js/Stats.js"></script>

		<script type="x-shader/x-vertex" id="vertexshader">

			attribute float size;
			attribute vec4 ca;

			varying vec4 vColor;

			void main() {

				vColor = ca;

				vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );

				gl_PointSize = size * ( 150.0 / length( mvPosition.xyz ) );

				gl_Position = projectionMatrix * mvPosition;

			}

		</script>

		<script type="x-shader/x-fragment" id="fragmentshader">

			uniform vec3 color;
			uniform sampler2D texture;

			varying vec4 vColor;

			void main() {

				vec4 outColor = texture2D( texture, gl_PointCoord );

				if ( outColor.a < 0.5 ) discard;

				gl_FragColor = outColor * vec4( color * vColor.xyz, 1.0 );

				float depth = gl_FragCoord.z / gl_FragCoord.w;
				const vec3 fogColor = vec3( 0.0 );

				float fogFactor = smoothstep( 200.0, 600.0, depth );
				gl_FragColor = mix( gl_FragColor, vec4( fogColor, gl_FragColor.w ), fogFactor );

			}

		</script>


		<script>

		if ( ! Detector.webgl ) Detector.addGetWebGLMessage();

		var renderer, scene, camera, stats;

		var object, uniforms, attributes;

		var vc1;

		var WIDTH = window.innerWidth,
			HEIGHT = window.innerHeight;

		init();
		animate();

		function init() {

			camera = new THREE.PerspectiveCamera( 40, WIDTH / HEIGHT, 1, 1000 );
			camera.position.z = 500;

			scene = new THREE.Scene();

			scene.add( camera );

			attributes = {

				size: {	type: 'f', value: [] },
				ca:   {	type: 'c', value: [] }

			};

			uniforms = {

				amplitude: { type: "f", value: 1.0 },
				color:     { type: "c", value: new THREE.Color( 0xffffff ) },
				texture:   { type: "t", value: 0, texture: THREE.ImageUtils.loadTexture( "textures/sprites/ball.png" ) },

			};

			uniforms.texture.texture.wrapS = uniforms.texture.texture.wrapT = THREE.RepeatWrapping;

			var shaderMaterial = new THREE.ShaderMaterial( {

				uniforms: 		uniforms,
				attributes:     attributes,
				vertexShader:   document.getElementById( 'vertexshader' ).textContent,
				fragmentShader: document.getElementById( 'fragmentshader' ).textContent

			});


			var radius = 100, inner = 0.6 * radius;
			var geometry = new THREE.Geometry();

			for ( var i = 0; i < 100000; i ++ ) {

				vector = new THREE.Vector3( Math.random() * 2 - 1, Math.random() * 2 - 1, Math.random() * 2 - 1 );

				vector.multiplyScalar( radius );

				if ( ( vector.x > inner || vector.x < -inner ) ||
				     ( vector.y > inner || vector.y < -inner ) ||
				     ( vector.z > inner || vector.z < -inner )  )

				geometry.vertices.push( new THREE.Vertex( vector ) );

			}

			vc1 = geometry.vertices.length;

			var m, dummyMaterial = new THREE.MeshFaceMaterial();

			radius = 200;
			var geometry2 = new THREE.CubeGeometry( radius, 0.1 * radius, 0.1 * radius, 50, 5, 5 );

			function addGeo( geo, x, y, z, ry ) {

				m = new THREE.Mesh( geo, dummyMaterial );
				m.position.set( x, y, z );
				m.rotation.y = ry;

				THREE.GeometryUtils.merge( geometry, m );

			}

			// side 1

			addGeo( geometry2, 0,  110,  110, 0 );
			addGeo( geometry2, 0,  110, -110, 0 );
			addGeo( geometry2, 0, -110,  110, 0 );
			addGeo( geometry2, 0, -110, -110, 0 );

			// side 2

			addGeo( geometry2,  110,  110, 0, Math.PI/2 );
			addGeo( geometry2,  110, -110, 0, Math.PI/2 );
			addGeo( geometry2, -110,  110, 0, Math.PI/2 );
			addGeo( geometry2, -110, -110, 0, Math.PI/2 );

			// corner edges

			var geometry3 = new THREE.CubeGeometry( 0.1 * radius, radius * 1.2, 0.1 * radius, 5, 60, 5 );

			addGeo( geometry3,  110, 0,  110, 0 );
			addGeo( geometry3,  110, 0, -110, 0 );
			addGeo( geometry3, -110, 0,  110, 0 );
			addGeo( geometry3, -110, 0, -110, 0 );

			// particle system

			object = new THREE.ParticleSystem( geometry, shaderMaterial );
			object.dynamic = true;

			// custom attributes

			var vertices = object.geometry.vertices;

			var values_size = attributes.size.value;
			var values_color = attributes.ca.value;

			for( var v = 0; v < vertices.length; v ++ ) {

				values_size[ v ] = 10;
				values_color[ v ] = new THREE.Color( 0xffffff );

				if ( v < vc1 ) {

					values_color[ v ].setHSV( 0.5 + 0.2 * ( v / vc1 ), 0.99, 1.0 );

				} else {

					values_size[ v ] = 55;
					values_color[ v ].setHSV( 0.1, 0.99, 1.0 );

				}

			}

			//console.log( vertices.length );

			scene.add( object );

			renderer = new THREE.WebGLRenderer( { clearColor: 0x000000, clearAlpha: 1 } );
			renderer.setSize( WIDTH, HEIGHT );

			var container = document.getElementById( 'container' );
			container.appendChild( renderer.domElement );

			stats = new Stats();
			stats.domElement.style.position = 'absolute';
			stats.domElement.style.top = '0px';
			container.appendChild( stats.domElement );

		}

		function animate() {

			requestAnimationFrame( animate );

			render();
			stats.update();

		}

		function render() {

			var time = Date.now() * 0.01;

			object.rotation.y = object.rotation.z = 0.02 * time;

			for( var i = 0; i < attributes.size.value.length; i ++ ) {

				if ( i < vc1 )
					attributes.size.value[ i ] = 26 + 32 * Math.sin( 0.1 * i + 0.6 * time );


			}

			attributes.size.needsUpdate = true;

			renderer.render( scene, camera );

		}


	</script>

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